1. Field of the Invention
The present invention relates to an injection molding machine, and in particular, to an injection molding machine having a structure in which a screw reciprocates smoothly axially.
2. Description of the Related Art
An injection molding machine includes a cylinder and a screw. The injection molding machine advances the screw in the cylinder and injects molten resin into a mold to mold a product. Thus, the injection molding machine includes a screw advancing and retracting mechanism advancing and retracting the screw inside the cylinder, and a screw rotation mechanism rotating the screw inside the cylinder in order to introduce resin pellets into the cylinder and to knead and melt the introduced resin pellets.
In a known injection molding machine, for example, an intermediate plate is supported on a slidable base (moving base) via a linear guide; a motor supporting the rear end of the screw via a bearing and rotationally driving the screw is attached to the intermediate plate. Furthermore, a linear motion mechanism advances and retracts the intermediate plate. Jpn. Pat. Appln. KOKAI Publication No. 2003-80559
However, if the intermediate plate to which the motor supporting and rotationally driving the screw advances and retracts on the sliding base via the linear guide, when the linear motion mechanism advances and retracts the intermediate plate, the intermediate plate travels inappropriately forward and backward, making the advancing and retracting operation of the screw unstable; this is due to a long distance between the position where the intermediate plate is supported on the sliding base and the positions where the screw and the motor are attached to the intermediate plate.